C/2018 A4 (PANSTARRS)

메타데이터

항목 값
Designation C/2018 A4 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2018-05-18T19:21:20.165760Z
Orbit solution date (soln_date, UTC) 2023-05-03T22:42:49Z
Obs used 79
NEO -
M1 8.400
K1 22.250
PC 0.030
Osculating 궤도요소
항목 값
Epoch (epoch_cal, TDB) 2018-01-15.0000000
e 0.80435873
q (au) 2.402567
a (au) 12.280471
i (deg) 3.148025
Ω (om, deg) 97.634759
ω (w, deg) 356.135345
M (ma, deg) 357.164531

밝기

C/2018 A4 (PANSTARRS) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (10.546 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목 값
H0 10.546
n 6.000
gf 1.000
gb -1.000
k 1.000
δ90 10.000
파라미터 기호 범위 설명
태양·지구거리 1 AU에서의 절대등급 H0 -5 to 20 혜성의 고유 밝기
광도 기울기 파라미터 n 2 to 6 태양거리 변화에 따른 밝기 변화율
전방 산란 비대칭 계수 gf 0.8 to 1 전방 산란의 강도
후방 산란 비대칭 계수 gb -1 to -0.5 후방 산란의 강도
분할 계수 k 0.8 to 1 전·후방 산란 기여도 비율
먼지/가스 밝기 비 δ90 1 to 10 코마에서 먼지 산란 대비 가스 방출의 상대 기여

참고: EPSC-DPS2025-160

천체력

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-09-20 00:00 16:15:46.00 -19:46:35.7 HIP 79690 18.02
2026-09-20 12:00 16:15:49.87 -19:46:48.7 HIP 79690 17.77
2026-09-21 00:00 16:15:53.79 -19:47:01.8 HIP 79690 17.57
2026-09-21 12:00 16:15:57.77 -19:47:15.0 HIP 79690 17.42
2026-09-22 00:00 16:16:01.80 -19:47:28.3 HIP 79690 17.32
2026-09-22 12:00 16:16:05.89 -19:47:41.7 HIP 79690 17.27
2026-09-23 00:00 16:16:10.04 -19:47:55.3 HIP 79690 17.28
2026-09-23 12:00 16:16:14.24 -19:48:09.0 HIP 79690 17.35
2026-09-24 00:00 16:16:18.49 -19:48:22.7 HIP 79690 17.49
2026-09-24 12:00 16:16:22.79 -19:48:36.6 HIP 79690 17.68
2026-09-25 00:00 16:16:27.15 -19:48:50.6 HIP 79690 17.94
2026-09-25 12:00 16:16:31.57 -19:49:04.8 HIP 79690 18.26
2026-09-26 00:00 16:16:36.03 -19:49:19.0 HIP 79788 17.78
2026-09-26 12:00 16:16:40.55 -19:49:33.3 HIP 79788 17.25
2026-09-27 00:00 16:16:45.12 -19:49:47.8 HIP 79788 16.78
2026-09-27 12:00 16:16:49.74 -19:50:02.3 HIP 79788 16.36
2026-09-28 00:00 16:16:54.42 -19:50:17.0 HIP 79788 16.00
2026-09-28 12:00 16:16:59.14 -19:50:31.8 HIP 79788 15.71
2026-09-29 00:00 16:17:03.92 -19:50:46.6 HIP 79788 15.51
2026-09-29 12:00 16:17:08.75 -19:51:01.6 HIP 79788 15.38
2026-09-30 00:00 16:17:13.62 -19:51:16.7 HIP 79788 15.35
2026-09-30 12:00 16:17:18.55 -19:51:31.9 HIP 79788 15.40
2026-10-01 00:00 16:17:23.53 -19:51:47.1 HIP 79788 15.55
2026-10-01 12:00 16:17:28.56 -19:52:02.5 HIP 79788 15.79
2026-10-02 00:00 16:17:33.64 -19:52:18.0 HIP 79788 16.12
2026-10-02 12:00 16:17:38.77 -19:52:33.5 HIP 79788 16.54
2026-10-03 00:00 16:17:43.95 -19:52:49.2 HIP 79788 17.05
2026-10-03 12:00 16:17:49.17 -19:53:05.0 HIP 79788 17.64
2026-10-04 00:00 16:17:54.45 -19:53:20.8 HIP 79788 18.30
2026-10-04 12:00 16:17:59.77 -19:53:36.8 HIP 79788 19.03
2026-10-05 00:00 16:18:05.14 -19:53:52.8 HIP 79788 19.82
2026-10-05 12:00 16:18:10.56 -19:54:08.9 HIP 79788 20.67
2026-10-06 00:00 16:18:16.03 -19:54:25.2 HIP 79788 21.58
2026-10-06 12:00 16:18:21.54 -19:54:41.5 HIP 79945 21.35
2026-10-07 00:00 16:18:27.10 -19:54:57.8 HIP 79945 20.47
2026-10-07 12:00 16:18:32.71 -19:55:14.3 HIP 79945 19.65
2026-10-08 00:00 16:18:38.36 -19:55:30.9 HIP 79945 18.87
2026-10-08 12:00 16:18:44.06 -19:55:47.5 HIP 79945 18.16
2026-10-09 00:00 16:18:49.80 -19:56:04.2 HIP 79945 17.52
2026-10-09 12:00 16:18:55.59 -19:56:21.0 HIP 79945 16.97
2026-10-10 00:00 16:19:01.43 -19:56:37.9 HIP 80019 15.90
2026-10-10 12:00 16:19:07.31 -19:56:54.9 HIP 80019 14.51
2026-10-11 00:00 16:19:13.23 -19:57:11.9 HIP 80019 13.13